Find the total surface area of a cube whose edge measure 20 cm.

Answer

To find the total surface area of a cube with an edge length of 20 cm, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the edge length of the cube**:
- Given: Edge length \( a = 20 \) cm.

2. **Recall the formula for the total surface area of a cube**:
- The formula for the total surface area \( A \) of a cube is:
\[ A = 6a^2 \]

3. **Substitute the edge length into the formula**:
- Substitute \( a = 20 \) cm into the formula:
\[ A = 6 \times (20)^2 \]

4. **Calculate \( (20)^2 \)**:
- Calculate the square of 20:
\[ (20)^2 = 400 \]

5. **Multiply by 6**:
- Now, multiply 400 by 6:
\[ A = 6 \times 400 = 2400 \]

6. **State the final answer**:
- The total surface area of the cube is:
\[ A = 2400 \text{ cm}^2 \]

### Final Answer:
The total surface area of the cube is \( 2400 \text{ cm}^2 \).

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